Photovoltaic module and preparation method

Abstract

The invention relates to a photovoltaic module and a preparation method thereof. The photovoltaic module comprises first packaging front plate glass, a front layer packaging adhesive film layer, a semi-finished product laminated piece, a rear layer packaging adhesive film layer and first packaging cover plate glass which are stacked in sequence, the semi-finished product laminated piece comprises second packaging front plate glass, a first adhesive film layer, a battery piece array layer, a second adhesive film layer and second packaging cover plate glass which are stacked in sequence; the second packaging front plate glass is attached to a front packaging adhesive film layer; the second packaging cover plate glass is attached to a rear packaging adhesive film layer; the second packaging front plate glass and the second packaging cover plate glass are made of non-tempered glass; the first packaging front plate glass and the first packaging cover plate glass are made of at least one of tempered glass or semi-tempered glass. According to the invention, the edge of the module has no overpressure phenomenon, the glass and the adhesive film have no stress concentration phenomenon, the thickness distribution is uniform, the phenomena of delamination, relaxation and the like caused by stress release of the edge of the module in an outdoor actual use environment can be prevented, and the reliability of the module is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a photovoltaic module and a preparation method thereof. Background Art

[0002] At present, the photovoltaic industry uniformly chooses to use tempered or semi-tempered glass to make double-glass modules. The main reason is that after tempering, the impact strength and bending strength of the glass are 3-5 times that of ordinary glass. Therefore, the mechanical strength of photovoltaic modules made of tempered glass is greatly improved, and the performance is better than that of ordinary glass.

[0003] Tempered glass is formed by ordinary glass after high-temperature heat treatment and annealing. During high-temperature heat treatment and annealing, different areas will be heated and cooled at different rates, resulting in different degrees of tempering in different areas.

[0004] Due to the different tempering effects of tempered glass in different areas, an obvious phenomenon will occur during the lamination process of photovoltaic double-glass modules: during the lamination process, the temperature of the double-glass modules reaches about 140°C. After the front and rear glasses are heated, due to the high temperature and inconsistent heating rates of the glass, the four sides of the front and rear glasses are warped, and the four corners are even worse. This causes the edge of the module to be subjected not only to the pressure applied by the laminator, but also to the additional force caused by the deformation of the glass edge. Therefore, after lamination, the edge of the double-glass module, its internal film will be abnormally squeezed, resulting in inconsistency between the thickness of the module edge and the thickness of the middle of the module, that is, the thickness of the module edge is less than the thickness of the middle of the module. This thickness difference will cause the module to have film delamination at the edge of the module during reliability testing and actual outdoor use environments, when subjected to long-term alternation of hot and cold environments, or even in extreme hot and cold climates, resulting in reduced sealing and waterproof performance of the module and reduced mechanical strength.

[0005] Therefore, it is necessary to design a photovoltaic module and a preparation method to solve the above-mentioned technical problems. Summary of the invention

[0006] Based on this, a photovoltaic module and a preparation method are provided to solve the problem of overpressure at the edge of the module and thickness lower than the thickness of the central area of ​​the module due to thermal deformation of the tempered glass during the lamination process of the photovoltaic module.

[0007] To solve the above problems, the present application provides a photovoltaic module, comprising: a first encapsulation front plate glass, a front encapsulation film layer, a semi-finished laminate, a rear encapsulation film layer and a first encapsulation cover glass stacked in sequence; the semi-finished laminate comprises a second encapsulation front plate glass, a first film layer, a cell array layer, a second film layer and a second encapsulation cover glass stacked in sequence; the second encapsulation front plate glass is bonded to the front encapsulation film layer; the second encapsulation cover glass is bonded to the rear encapsulation film layer; wherein, the second encapsulation front plate glass and the second encapsulation cover glass are made of non-tempered glass; the first encapsulation front plate glass and the first encapsulation cover glass are made of at least one of tempered or semi-tempered glass.

[0008] A preferred solution is that the thickness of the first encapsulation front plate glass and the first encapsulation cover plate glass is set to 0.5-2.0 mm.

[0009] A preferred solution is that the thickness of the second encapsulation front plate glass and the second encapsulation cover plate glass is set to 0.5-2.0 mm.

[0010] A preferred solution is that the front packaging film layer and the rear packaging film layer are made of hot melt adhesive, pressure sensitive adhesive or liquid silicone.

[0011] A preferred solution is that the first adhesive film layer and the second adhesive film layer are made of hot melt adhesive.

[0012] A preferred solution is that the battery cell array layer includes multiple battery cells and solder ribbons that connect the individual battery cells into a string; and the second encapsulation front glass and / or the second encapsulation cover glass are provided with a solder ribbon placement groove for placing the solder ribbon on one side close to the battery cell array layer.

[0013] A preferred solution is that the cell array layer also includes a bus bar connected to a welding strip; and a bus bar placement groove for placing the bus bar is also provided on a side of the second encapsulation front glass and / or the second encapsulation cover glass close to the cell array layer.

[0014] A preferred solution is that the solder ribbon placement groove is continuously extended along the direction of placement of the solder ribbon on the second encapsulation front glass plate and / or the second encapsulation cover glass; and the solder ribbon placement groove is arranged one-to-one with the solder ribbon on the battery cell array layer.

[0015] A preferred solution is that the cross section of the welding strip placement groove is arc-shaped.

[0016] A preferred solution is that the opening width of the solder strip placement groove is greater than the diameter of the solder strip.

[0017] A preferred solution is that a glaze layer or a film layer is provided on any one or both sides of the second encapsulation cover glass; the position of the glaze layer or the film layer corresponds to the gap between the multiple cells of the cell array layer.

[0018] The present application also provides a method for preparing a photovoltaic module, the method comprising the following steps:

[0019] Making a semi-finished laminate: laying a second encapsulation front plate glass, a first adhesive film layer, a cell array layer, a second adhesive film layer, and a second encapsulation cover plate glass in sequence, and laminating at a first temperature to obtain a semi-finished laminate, wherein the second encapsulation front plate glass and the second encapsulation cover plate glass are made of non-tempered glass;

[0020] Making a finished laminate: laying the first encapsulation front plate glass, the front encapsulation film layer, the semi-finished laminate, the rear encapsulation film layer, and the first encapsulation cover glass in sequence, and laminating at a second temperature to obtain a finished laminate, wherein the first encapsulation front plate glass and the first encapsulation cover glass are at least one of tempered glass or semi-tempered glass.

[0021] Preferably, the first temperature is higher than the second temperature.

[0022] Beneficial effects:

[0023] The lamination process of the photovoltaic module is divided into two steps. First, the second encapsulation front plate glass, the first adhesive film layer, the battery cell array layer, the second adhesive film layer and the second encapsulation cover glass are laminated to form a semi-finished laminate. Since the second encapsulation front plate glass and the second encapsulation cover glass used to make the semi-finished laminate are made of non-tempered glass, the surface stress of this material is low, and the glass will not warp or deform at the edges during the lamination and heating process, and the glass still remains flat as a whole. The edge thickness of the semi-finished laminate thus made is equal to the internal center thickness, that is, the edge of the module will not produce overpressure; then, the first encapsulation front plate glass, the front encapsulation film layer, the back encapsulation film layer and the first encapsulation cover glass are laminated with the semi-finished laminate, and laminated again to form a finished laminate, that is, a module. Since the first encapsulation front plate glass and the first encapsulation cover glass are made of tempered glass or semi-tempered glass, the impact resistance and bending resistance of the optical module can be improved, thereby improving the performance of the module. There is no overpressure on the edge of the component, no stress concentration on the glass and film, and the thickness is evenly distributed. This can prevent delamination and relaxation caused by stress release at the edge of the component in actual outdoor use environments, thereby improving component reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the structure of the photovoltaic module in this embodiment;

[0025] Figure 2 is a schematic structural diagram of a semi-finished laminate in this embodiment;

[0026] Figure 3 is a schematic cross-sectional view of a semi-finished laminated component when no placement grooves are provided on the second encapsulation front plate glass and the second encapsulation cover plate glass in this embodiment;

[0027] Figure 4 It is a cross-sectional schematic diagram of a semi-finished laminated component when placement grooves are provided on the second encapsulation front plate glass and the second encapsulation cover plate glass in this embodiment;

[0028] Figure 5 is a cross-sectional schematic diagram of the second encapsulation front glass in this embodiment;

[0029] Figure 6 FIG. 4 is a schematic cross-sectional view of the second packaging cover glass in this embodiment.

[0030] Figure numerals: 10, photovoltaic module; 11, first encapsulation front glass; 12, front encapsulation film layer; 13, semi-finished laminate; 131, second encapsulation front glass; 132, first film layer; 133, battery cell array layer; 1331, battery cell; 1332, welding ribbon; 134, second film layer; 135, second encapsulation cover glass; 14, rear encapsulation film layer; 15, first encapsulation cover glass; 16, welding ribbon placement groove. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0032] It should be noted that the illustrations provided in this embodiment only illustrate the basic concept of the present application in a schematic manner, and therefore the drawings only show components related to the present application rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0033] The directions or positional relationships indicated by the terms "upper", "lower", "left", "right", "middle", "longitudinal", "lateral", "horizontal", "inner", "outer", "radial", "circumferential" and the like in this specification are based on the directions or positional relationships shown in the drawings and are only for the convenience of simplifying the description. They do not indicate or imply that the devices or elements referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0034] In order to solve the problem in the prior art that the edge of the double-glass component is curled and deformed when the tempered glass is laminated and heated, resulting in overpressure on the edge of the component, so that the thickness of the edge adhesive film is less than the middle thickness.

[0035] Therefore, in response to the above problems, the embodiments of the present application provide a photovoltaic module and a preparation method to solve the problem of overpressure on the edge of the photovoltaic double-glass module and thickness being lower than the thickness of the central area of ​​the module due to thermal deformation of the tempered glass during the lamination process.

[0036] The present application provides a photovoltaic module. The photovoltaic module provided in this embodiment is described in detail below in conjunction with the accompanying drawings. Figure 1 , Figure 2 As shown, the photovoltaic module 10 includes: a first encapsulation front plate glass 11, a front encapsulation film layer 12, a semi-finished laminate 13, a rear encapsulation film layer 14 and a first encapsulation cover glass 15 which are stacked in sequence; the semi-finished laminate 13 includes a second encapsulation front plate glass 131, a first film layer 132, a cell array layer 133, a second film layer 134 and a second encapsulation cover glass 135 which are stacked in sequence; the second encapsulation front plate glass 131 is bonded to the front encapsulation film layer 12; the second encapsulation cover glass 135 is bonded to the rear encapsulation film layer 14; wherein, the second encapsulation front plate glass 131 and the second encapsulation cover glass 135 are made of non-tempered glass, and the first encapsulation front plate glass 11 and the first encapsulation cover glass 15 are made of tempered glass or semi-tempered glass.

[0037] The present application also provides a method for preparing the above photovoltaic module, the method comprising the following steps:

[0038] Step 1, making a semi-finished laminate 13: laying a second encapsulation front plate glass 131, a first adhesive film layer 132, a cell array layer 133, a second adhesive film layer 134, and a second encapsulation cover plate glass 135 in sequence, and laminating at a first temperature to obtain a semi-finished laminate 13, wherein the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135 are made of non-tempered glass;

[0039] Step 2, making a finished laminate: laying the first encapsulation front glass 11, the front encapsulation film layer 12, the semi-finished laminate 13, the rear encapsulation film layer 14, and the first encapsulation cover glass 15 in sequence, and laminating at a second temperature to obtain a finished laminate, wherein the first encapsulation front glass 11 and the first encapsulation cover glass 15 are at least one of tempered glass or semi-tempered glass.

[0040] In the embodiment of the present application, the lamination process of the photovoltaic module 10 is divided into two steps. First, the first round of lamination is carried out in the stacking order of the second encapsulation front plate glass 131, the first adhesive film layer 132, the cell array layer 133, the second adhesive film layer 134 and the second encapsulation cover glass 135 to form a semi-finished laminate 13. The temperature of the first round of lamination is the first temperature, and the first lamination temperature can be 120-230°C. Since the second encapsulation front plate glass 131 and the second encapsulation cover glass 135 in the semi-finished laminate 13 are made of non-tempered glass, this kind of glass will not deform to different degrees during the lamination and heating process due to different tempering degrees. The glass will not bend or deform at the edge when heated, and the overall flatness will be maintained. The edge thickness of the semi-finished laminate 13 thus made is equal to the internal center thickness, that is, the edge of the component will not produce overpressure; then the front encapsulation film layer 12 is first laid on the first encapsulation front plate glass 11, and then the cooled semi-finished laminate 13 is The semi-finished laminate 13 is laid on the front packaging film layer 12, and the second packaging front plate glass 131 is bonded to the front packaging film layer 12, and then the rear packaging film layer 14 and the first packaging cover glass 15 are laid in sequence on the second packaging cover glass 135 above the semi-finished laminate 13. After laying, the components are subjected to a second round of lamination to form a finished laminate, that is, the final photovoltaic component 10. The temperature of the second lamination is a second temperature, and the second temperature depends on the type of the front packaging film layer 12 and the rear packaging film layer 14, but the second temperature is lower than the first temperature, so that the first packaging cover glass 15 and the second packaging cover glass 134 can be combined together, and the first packaging front plate glass 11 and the second packaging front plate glass 131 can be combined together at a low temperature. At the same time, the first packaging front plate glass 11 and the first packaging cover glass 15 will not be deformed, and the first film layer 132 and the second film layer 134 will not soften, and the semi-finished laminate 13 will not be damaged.

[0041] In this embodiment, it should be noted that a first encapsulation front glass 11 and a first encapsulation cover glass 15 are arranged on both sides of the semi-finished laminate 13, and tempered or semi-tempered glass is used. The impact resistance and bending strength of this glass material are better than those of ordinary glass. Therefore, the glass as the external contact surface can achieve multiple protections for the power generation unit, that is, there are two layers of glass on the front and back sides of the cell array layer 133 as encapsulation protection layers. Even if the outermost encapsulation glass is damaged by external factors, there is still glass encapsulation protection for the cell array layer 133 inside the photovoltaic module 10, which greatly improves the life and risk resistance of the photovoltaic module 10.

[0042] In an alternative embodiment, the impact resistance of the second front encapsulation glass 131 is lower than that of the first front encapsulation glass 11. For example, the second front encapsulation glass 131 may be ordinary non-tempered glass, the first front encapsulation glass 11 is tempered glass, the thickness of the second front encapsulation glass 131 is a1, the thickness of the first front encapsulation glass is a2, a1 < a2, and the value of a1 + a2 is less than or equal to 3.2.

[0043] The impact resistance of the second cover encapsulation glass 135 is lower than that of the first cover encapsulation glass 15. For example, the second cover encapsulation glass 135 is ordinary non-tempered glass, and the first cover encapsulation glass 15 is tempered glass.

[0044] In this embodiment, it should also be noted that the thicknesses of the first front encapsulation glass 11 and the first cover encapsulation glass 15 are set to 0.5 - 2.0 mm; and / or, the thicknesses of the second front encapsulation glass 131 and the second cover encapsulation glass 135 are also set to 0.5 - 2.0 mm. Currently, the glass thickness dimensions of conventional photovoltaic modules have reached 1.6 or 2.0 mm; therefore, in this embodiment, based on the principle of cost reduction, the upper limit dimensions of the thicknesses of the first front encapsulation glass 11, the first cover encapsulation glass 15, the second front encapsulation glass 131, and the second cover encapsulation glass 135 are set to not greater than 2.0 mm.

[0045] In some embodiments, the unit area weight of the front encapsulation film layer 12 and the rear encapsulation film layer 14 is less than 300 g / m 2 , and / or the unit area weight of the first film layer 132 and the second film layer 134 is also less than 300 g / m 2 . Currently, the weight limit of the film for conventional photovoltaic modules is around 300 g / m 2 . Since the film needs to have a certain thickness to wrap the solder tape (the diameter of the solder tape is generally about 0.2 mm), and at the same time, if the film is too thin, the product quality of the module cannot be guaranteed. Therefore, in this embodiment, the unit area weights of the front encapsulation film layer 12, the rear encapsulation film layer 14, the first film layer 132, and the second film layer 134 are set to be less than 300 g / m 2 , which can reduce the film usage and save costs.

[0046] In the present embodiment, it should also be noted that the photovoltaic module 10 in the present embodiment adopts step-by-step lamination. The first step is to make a semi-finished laminate 13, and the second step is to laminate the semi-finished laminate 13 for a second time to form a finished laminate. The purpose of the second round of lamination is to package the semi-finished laminate 13 with the remaining packaging materials such as the first packaging front plate glass 11, the front packaging film layer 12, the rear packaging film layer 14 and the first packaging cover glass 15 together to form a whole. At this time, the battery cell array layer 133 as the power generation unit has been packaged in the semi-finished laminate 13, and the temperature of the second round of lamination does not need to be consistent with the temperature of the semi-finished laminate 13 when it is laminated. In order to prevent the semi-finished laminate 13 from deforming or the formed film from melting during the second lamination process, the temperature of the second lamination should be lower than the temperature of the first lamination. For example, hot melt adhesive, pressure sensitive adhesive, and liquid silicone can be used, wherein the process temperature of the hot melt adhesive should be lower than the process temperature of the first film and the second film, for example, it can be a quick-crosslinking film of 50 to 100°C. The purpose of using low temperature in the above process is to reduce the influence of temperature on the semi-finished laminate 13, the first package front glass 11 and the first package cover glass 15, to prevent the softening of the adhesive film in the semi-finished laminate 13, and to prevent the first package front glass 11 and the first package cover glass 15 from being deformed by heat. The degree of deformation of the first package front glass 11 and the first package cover glass 15 is low, so that the edge thickness of the components of the final finished laminate is consistent with the center thickness of the components, and the edge overpressure phenomenon is solved.

[0047] In some embodiments, the first adhesive film layer 132 and the second adhesive film layer 134 use hot melt adhesive, for example, including heat-crosslinked materials or thermoplastic materials; wherein the heat-crosslinked materials may include ethylene-vinyl acetate copolymer, polyolefin elastomer, liquid silicone; the thermoplastic material may include polyvinyl butyral, thermoplastic polyolefin elastomer.

[0048] Please refer to Figure 2-Figure 4 As shown, in this embodiment, it is also necessary to explain that the battery cell array layer 133 includes a plurality of battery cells 1331 arranged in rows, and the battery cells 1331 are connected in series into battery strings through welding ribbons 1332, and the battery strings are then connected in series or in parallel through bus bars; the second encapsulation front plate glass 131 and / or the second encapsulation cover plate glass 135 are provided with a welding ribbon placement groove 16 for placing the welding ribbon 1332 on one side close to the battery cell array layer 133, and the second encapsulation front plate glass 131 and / or the second encapsulation cover plate glass 135 are also provided with a bus bar placement groove (not shown in the figure) for placing the bus bar on one side close to the battery cell array layer 133.

[0049] When the photovoltaic module is packaged and laminated, the welding strip 1332 on the side corresponding to the battery cell 1331 and the second packaging front glass 131 and / or the second packaging cover glass 135 can be embedded in the welding strip placement groove 16; the bus bars at both ends of the battery string on the side corresponding to the battery cell 1331 and the second packaging front glass 131 and / or the second packaging cover glass 135 can be embedded in the bus bar placement groove, thereby reducing the hidden cracks and breakage of the battery cell 1331 during the packaging and lamination of the photovoltaic module, improving the product yield and quality, and reducing the thickness of the packaging film layer, reducing the amount of packaging materials used, and reducing the cost of the module.

[0050] Specifically, in this embodiment, it is preferred that a soldering tape placement groove 16 is correspondingly provided on the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135. The provision of the soldering tape placement groove 16 can accommodate the soldering tape 1332. On the one hand, the soldering tape 1332 is separated from the inner wall of the soldering tape placement groove 16 and the space between the two is filled with adhesive; on the other hand, the soldering tape 1332 has been accommodated in the soldering tape placement groove 16, and during the lamination process, it can be avoided that the soldering tape 1332 and the glass, i.e., the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135, first contact and form extrusion, thereby causing the battery cell 1331 to break, thereby improving the thermal cycle resistance of the photovoltaic module 10 and improving the product yield. In addition, referring to Figure 3 and Figure 4 As shown, by setting the soldering ribbon placement groove 16, the thickness of the first adhesive film layer 132 and the second adhesive film layer 134 can be reduced, because the height of the soldering ribbon 1332 protrusion has been accommodated in the soldering ribbon placement groove 16, so the thickness of the first adhesive film layer 132 between the second encapsulation front plate glass 131 and the battery cell 1331 and the second adhesive film layer 134 between the second encapsulation cover plate glass 135 and the battery cell 1331 can be greatly reduced. For example, for a conventional encapsulated photovoltaic module 10, when a 0.26mm diameter soldering ribbon 1332 is used, the thickness limit of the (EVA) encapsulation film is 320-360g / m 2 The thickness of the laminated film is approximately equal to the diameter of the welding tape; in this embodiment, the thickness of the first film layer 132 and the second film layer 134 can be reduced to 200g / m 2 There is no lower limit below, and it is only necessary that the adhesive film achieves a good bonding effect between the battery cell 1331 and the glass.

[0051] Please refer to Figure 4-Figure 6 As shown in one achievable manner, since the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135 are made of non-tempered glass, the welding strip placement groove 16 can be easily etched on the side of the battery cell 1331, and then the welding strip placement groove 16 can be used to accommodate the fixed welding strip 1332 (refer to the schematic diagram Figure 4), such a setting can not only reduce the amount of packaging film used and achieve cost reduction, but also achieve higher reliability of the components.

[0052] In one example, the solder ribbon placement groove 16 is continuously extended along the extension direction of the solder ribbon 1332 when it is placed on the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135, and is arranged one-to-one with the solder ribbon 1332 on the battery cell array layer 133. The solder ribbon placement groove 16 that is continuously extended can accommodate the entire solder ribbon 1332, thereby achieving the effect of reducing the amount of adhesive film used.

[0053] Please continue to refer to Figure 4-Figure 6 As shown, in an achievable manner, the solder strip placement grooves 16 are arranged in parallel and spaced apart in a plurality of groups on the second encapsulation front plate glass 131 and the second encapsulation cover plate glass 135 along the arrangement direction of the solder strips 1332, and each group of solder strip placement grooves 16 is arranged in one-to-one correspondence with the solder strips 1332 on the battery cell 1331. When arranging, the solder strips 1332 are arranged in a plurality of groups, and each group of solder strips 1332 has a certain interval between adjacent ones, and then by providing a plurality of groups of solder strip placement grooves 16 for placing each solder strip 1332, contact between adjacent solder strips 1332 can be avoided.

[0054] In one example, the shape of the solder strip 1332 is generally set to be circular or approximately circular, that is, elliptical. Then, in order to match the shape of the solder strip 1332, in this embodiment, the solder strip placement groove 16 is set to be an arc groove, and the cross section of the solder strip placement groove 16 is arc-shaped. The circular or nearly circular solder strip 1332 can reflect the light irradiated on the circular or nearly circular solder strip 1332 to the battery cell 1331 for secondary use, thereby improving the utilization rate of light; in order to facilitate the processing of the solder strip placement groove 16 and form it in one time, the cross section of the solder strip placement groove 16 is selected to be arc-shaped, and the arc shape is a part of the circle or ellipse. In this way, using the solder strip placement groove 16 with an arc-shaped cross section can leave enough space between the solder strip placement groove 16 and the solder strip 1332 to fill an appropriate amount of packaging film, thereby achieving the effect of reducing the probability of the battery cell 1331 cracking.

[0055] In another example, the opening width of the solder strip placement groove 16 is set to be larger than the diameter of the solder strip 1332, and the depth of the solder strip placement groove 16 is equal to or smaller than the diameter of the solder strip 1332. Preferably, the depth of the solder strip placement groove 16 is equal to the diameter of the solder strip 1332. Of course, the solder strip placement groove 16 may not completely accommodate the solder strip 1332 during the lamination process. The purpose is to allow the adhesive film to have a certain squeezing effect on the solder strip 1332 during the lamination of the semi-finished laminate 13, so as to ensure that the solder strip 1332 and the battery cell 1331 are in full contact. Since the opening width of the solder strip placement groove 16 is larger than the diameter of the solder strip 1332, on the one hand, it is convenient for the solder strip 1332 to be fixed in the solder strip placement groove 16, and on the other hand, there is a gap between the two sides of the solder strip 1332 and the side wall of the solder strip placement groove 16, so that the adhesive film can flow in to ensure that there is enough packaging adhesive film between the solder strip 1332 and the solder strip placement groove 16. In other embodiments, the depth of the solder strip placement groove 16 can also be set to be greater than the diameter of the solder strip 1332, so that the solder strip 1332 can be completely accommodated in the solder strip placement groove 16, and there is also space between the groove bottom of the solder strip placement groove 16 and the solder strip 1332 to fill an appropriate amount of packaging film, thereby avoiding the solder strip 1332 contacting the glass first during the lamination process to form an extrusion, thereby causing the battery cell 1331 to break.

[0056] The busbar placement grooves correspond to the busbars one by one, and the shape of the busbar placement grooves matches the shape of the busbars. The size of the busbar placement grooves is larger than the size of the busbars, so that the busbars can be placed in the busbar placement grooves.

[0057] Please refer to Figure 1 , Figure 2 As shown, in this embodiment, it is also necessary to explain that a glaze layer or a film layer is provided on any one side or both sides of the second encapsulation cover glass 135, and the position of the glaze layer or the film layer corresponds to the gap between the battery cell array layers 133.

[0058] When a glaze layer is provided, the glaze layer is printed on any one side or both sides of the second encapsulation cover glass 135 , and the glaze layer can be provided as a white glaze layer.

[0059] When a film layer is provided, the film layer is attached to any one side or both sides of the second packaging cover glass 135 . The film layer can be formed by a colored packaging film such as a white or black film.

[0060] Through the above-mentioned arrangement, the incident light in the non-battery area of ​​the cell array layer 133 can be utilized, and no colored grid material or gap film is provided on the first encapsulation cover glass 15, so that the uniformity of the tempering degree of the first encapsulation cover glass 15 can be ensured as much as possible. By utilizing the gap light to increase the component power, the stability of the first encapsulation cover glass 15 against thermal shock and mechanical shock can be improved.

[0061] The implementation principle of this embodiment: When the photovoltaic module 10 is manufactured, the first step is to manufacture the semi-finished laminate 13, first lay the second encapsulation front plate glass 131, then lay the first adhesive film layer 132, then lay the battery array layer 133, and finally lay the second adhesive film layer 134 and the second encapsulation cover glass 135. At this time, the laid semi-finished laminate 13 is sent to the laminator for lamination. Since the second encapsulation front plate glass 131 and the second encapsulation cover glass 135 applied to the semi-finished laminate 13 are ordinary non-tempered glass, during the lamination process, the glass is heated without the behavior of warping and deformation on the four sides, and the glass remains flat as a whole. Then, other auxiliary means are used, such as the use of lamination auxiliary tooling, that is, the lamination frame combined with the mechanical platen laminator, to apply uniform pressure to the module. Finally, the thickness of the edge of the semi-finished laminate 13 after lamination is consistent with the thickness of the central area;

[0062] The second step is to make a finished laminate, that is, a formal assembly. First, the front encapsulation film layer 12 is laid on the first encapsulation front plate glass 11, and then the cooled semi-finished laminate 13 is laid on the front encapsulation film layer 12, and the second encapsulation front plate glass 131 is bonded to the front encapsulation film layer 12, and then the rear encapsulation film layer 14 and the first encapsulation cover glass 15 are laid in sequence on the semi-finished laminate 13, that is, on the second encapsulation cover glass 135. After the laying is completed, the assembly is subjected to a second round of lamination. During the second round of lamination, the semi-finished laminate 13 and the remaining encapsulation materials are encapsulated again to form a whole. At this time, the lamination temperature does not need to be the same as that of the semi-finished laminate 13. The temperature during lamination is kept consistent. By reasonably selecting the materials of the front encapsulation film layer 12 and the rear encapsulation film layer 14, when a lower lamination temperature, such as 50-100°C, is applied, and a certain pressure is applied by a laminator, the front encapsulation film layer 12 and the rear encapsulation film layer 14 can be quickly melted and the first encapsulation front plate glass 11, the first encapsulation cover plate glass 15 and the semi-finished laminate 13 are quickly bonded to form a whole. Due to the low process temperature, the deformation degree of the first encapsulation front plate glass 11 and the first encapsulation cover plate glass 15 is low, so that the edge thickness of the final finished laminate is consistent with the center thickness of the component, and the edge overpressure phenomenon is solved.

[0063] By using non-tempered glass in the first lamination step, the problem of glass edge deformation during lamination, which causes the thickness of the adhesive film on both sides of the cell array layer to become thinner in the edge area and affects the quality of the module, can be avoided. By using tempered glass in the second lamination step, while ensuring that the semi-finished laminated parts formed by the first lamination step are not damaged, lamination is performed at a lower temperature to combine the tempered glass with the non-tempered glass, and the outstanding impact resistance and bending resistance of the tempered glass are used to protect the module.

[0064] Therefore, in this embodiment, step-by-step lamination is adopted and combined with non-tempered glass, so that there is no overpressure phenomenon on the edge of the component, and the thickness of the edge of the component is the same as the thickness of the center area of ​​the component, which can improve the yield and reliability of the component.

[0065] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0066] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A photovoltaic module, characterized in that: include: A first encapsulation front plate glass (11), a front encapsulation film layer (12), a semi-finished laminate (13), a rear encapsulation film layer (14) and a first encapsulation cover plate glass (15) are sequentially stacked; The semi-finished laminate (13) comprises a second encapsulation front plate glass (131), a first adhesive film layer (132), a cell array layer (133), a second adhesive film layer (134) and a second encapsulation cover plate glass (135) which are stacked in sequence; The second encapsulation front plate glass (131) is adhered to the front encapsulation film layer (12); The second packaging cover glass (135) is bonded to the rear packaging film layer (14); Wherein, the second encapsulation front plate glass (131) and the second encapsulation cover plate glass (135) are made of non-tempered glass; The first encapsulation front plate glass (11) and the first encapsulation cover plate glass (15) are made of at least one of tempered glass and semi-tempered glass.

2. The photovoltaic module according to claim 1, characterized in that: include: The thickness of the first encapsulation front plate glass (11) and the first encapsulation cover plate glass (15) is set to 0.5-2.0 mm; And / or, the thickness of the second encapsulation front plate glass (131) and the second encapsulation cover plate glass (135) is set to 0.5-2.0 mm.

3. The photovoltaic module according to claim 1, characterized in that: The front packaging film layer (12) and the rear packaging film layer (14) are made of hot melt adhesive, pressure sensitive adhesive or liquid silicone; and / or, The first adhesive film layer (132) and the second adhesive film layer (134) are made of hot melt adhesive.

4. The photovoltaic module according to any one of claims 1 to 3, characterized in that: The battery cell array layer (133) comprises a plurality of battery cells (1331) and a welding strip (1332) for connecting the battery cells (1331) into a series; A soldering ribbon placement groove (16) for placing the soldering ribbon (1332) is provided on one side of the second packaging front glass (131) and / or the second packaging cover glass (135) close to the battery cell array layer (133).

5. The photovoltaic module according to any one of claims 1 to 3, characterized in that: The battery cell array layer (133) also includes a bus bar connected to the welding ribbon (1332); A bus bar placement groove for placing the bus bar is also provided on one side of the second encapsulation front plate glass (131) and / or the second encapsulation cover plate glass (135) close to the cell array layer (133).

6. The photovoltaic module according to claim 4, characterized in that: include: The solder strip placement groove (16) is continuously extended on the second encapsulation front plate glass (131) and / or the second encapsulation cover plate glass (135) along the extension direction of the solder strip (1332) when it is placed; The welding strip placement grooves (16) are arranged in one-to-one correspondence with the welding strips (1332) on the battery cell array layer (133).

7. The photovoltaic module according to claim 6, characterized in that: The cross section of the welding strip placement groove (16) is arc-shaped; And / or, the opening width of the welding strip placement groove (16) is greater than the diameter of the welding strip (1332).

8. The photovoltaic module according to claim 7, characterized in that: Any one of the two opposite sides of the second encapsulation cover glass (135) or both sides are provided with a glaze layer or a film layer; The position of the glaze layer or the film layer corresponds to the gap between the multiple battery cells (1331) of the battery cell array layer (133).

9. A method for preparing a photovoltaic module according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: Manufacturing a semi-finished laminate (13): sequentially laying a second encapsulation front plate glass (131), a first adhesive film layer (132), a cell array layer (133), a second adhesive film layer (134), and a second encapsulation cover plate glass (135), and laminating at a first temperature to obtain a semi-finished laminate (13), wherein the second encapsulation front plate glass (131) and the second encapsulation cover plate glass (135) are made of non-tempered glass; Manufacturing a finished laminate: laying a first encapsulation front plate glass (11), a front encapsulation film layer (12), a semi-finished laminate (13), a rear encapsulation film layer (14), and a first encapsulation cover plate glass (15) in sequence, and laminating at a second temperature to obtain a finished laminate, wherein the first encapsulation front plate glass (11) and the first encapsulation cover plate glass (15) are at least one of tempered glass or semi-tempered glass. 10 . The method for preparing a photovoltaic module according to claim 9 , wherein the first temperature is higher than the second temperature.

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